3 canned chipotle chiles in adobo, seeded and finely chopped, with 2
teaspoons of the adobo sauce
3 tablespoons finely chopped fresh cilantro
1/2 teaspoon sugar
Heat a large cast-iron skillet. When it is very hot, add the tomatillos, garlic cloves, tomatoes and onion and cook over low heat, turning frequently, until blackened in spots and softened, 8 to 10 minutes. Transfer the vegetables to a plate and let cool.
Put the tomatillos, garlic, tomatoes and onion in a food processor and pulse until coarsely chopped. Add the chipotles and adobo sauce, cilantro, salt and sugar and pulse just until combined.
The salsa can be refrigerated in an airtight container for up to 2 days.